Q. How many people can comfortably see a Television broadcast?
A. Any RCA Victor Television Receiver will enable the average family to see a program simultaneously.

This is from an actual brochure for RCA’s newest entertainment product, the Television, which it would introduce at the World’s Fair in New York City. On this date in 1939, Franklin Delano Roosevelt opened the fair and became the first president on a broadcast.

There are a few names to know when it comes to television. There’s Scotsman John Logie Baird, who gave the first mechanical television demonstration in January 1926. It broadcast images using disks to vary the amount of light in a given area.

And in September 1928, American Philo T. Farnsworth unveiled his electronic television, which used a tube. It would soon become the dominant breed of television.

The boob tube didn’t catch on until RCA’s big push at the 1939-40 World’s Fair at Flushing Meadows, Queens. With the slogan Dawn of a New Day, this brainchild of Robert Moses – set atop what once was the “valley of ashes” immortalized in The Great Gatsby – was the perfect place to introduce the invention to the masses.